中文语音识别的问题？？

using System;
using System.Collections.Generic;
using System.Text;namespace SpeachTemp
{
    class Speach_temp
    {
        private static Speach_temp _Instance = null;
        private SpeechLib.SpVoiceClass voice = null;
        private Speach_temp()
        {
            BuildSpeach();
        }
        public static Speach_temp instance()
        {            if (_Instance == null)                _Instance = new Speach_temp();            return _Instance;        }
        private void SetChinaVoice()
        {            voice.Voice = voice.GetVoices(string.Empty, string.Empty).Item(0);        }
        private void SetEnglishVoice()
        {            voice.Voice = voice.GetVoices(string.Empty, string.Empty).Item(1);        }
        public void SpeakChina(string strSpeak)
        {            SetChinaVoice();            Speak(strSpeak);        }
        private void SpeakEnglishi(string strSpeak)
        {            SetEnglishVoice();            Speak(strSpeak);        }
        public void AnalyseSpeak(string strSpeak)
        {            int iCbeg = 0;            int iEbeg = 0;            bool IsChina = true;            for (int i = 0; i < strSpeak.Length; i++)
            {                char chr = strSpeak[i];                if (IsChina)
                {                    if (chr <= 122 && chr >= 65)
                    {                        int iLen = i - iCbeg;                        string strValue = strSpeak.Substring(iCbeg, iLen);                        SpeakChina(strValue);                        iEbeg = i;                        IsChina = false;                    }                }                else
                {                    if (chr > 122 || chr < 65)
                    {                        int iLen = i - iEbeg;                        string strValue = strSpeak.Substring(iEbeg, iLen);                        this.SpeakEnglishi(strValue);                        iCbeg = i;                        IsChina = true;                    }                }            }//end for            if (IsChina)
            {                int iLen = strSpeak.Length - iCbeg;                string strValue = strSpeak.Substring(iCbeg, iLen);                SpeakChina(strValue);            }            else
            {                int iLen = strSpeak.Length - iEbeg;                string strValue = strSpeak.Substring(iEbeg, iLen);                SpeakEnglishi(strValue);            }        }
        public void BuildSpeach()
        {            if (voice == null)                voice = new SpeechLib.SpVoiceClass();        }
        public int Volume
        {            get
            {                return voice.Volume;            }            set
            {                voice.SetVolume((ushort)(value));            }        }
        public int Rate
        {            get
            {                return voice.Rate;            }            set
            {                voice.SetRate(value);            }        }
        public void Speak(string strSpeack)
        {            try
            {                voice.Speak(strSpeack, SpeechLib.SpeechVoiceSpeakFlags.SVSFlagsAsync);            }            catch (Exception err)
            {                throw (new Exception("发生一个错误：" + err.Message));            }        }
        public void Stop()
        {            voice.Speak(string.Empty, SpeechLib.SpeechVoiceSpeakFlags.SVSFPurgeBeforeSpeak);        }        public void Pause()
        {            voice.Pause();        }        public void Continue()
        {            voice.Resume();        }
    }
}using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;namespace SpeachTemp
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }        private void button1_Click(object sender, EventArgs e)
        {
            Speach_temp speach = new Speach_temp();//提示这里出错。
            speach.SpeakChina(textBox1.Text.Trim());
        }
    }
}
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